During the liquid crystal panel manufacturing process, the glass substrate 1 is usually transferred by a substrate transfer system. The existing substrate transfer system usually comprises a frame 5, a number of roller assemblies arranged side by side, and a controller 6 for controlling the roller assembly 6.
As shown in FIG. 1, the roller assembly comprises a drive motor 2, a shaft 3 driven by the drive motor 2, and a roller 4 sleeved on the shaft 3. The controller 6 is used to control rotation of the drive motor 2, so as to drive the shaft 3 to rotate, drive the roller 4 to rotate, and then drive the glass substrate 1 placed on the roller 4 to go forward by the friction of the roller 4, thus transferring the substrate.
As shown in FIG. 2, in order to control transfer speed, position, etc. of the glass substrate 1, a deceleration sensor 7, a positioning sensor 8, etc. are further arranged at appropriate positions of the frame 5. When the glass substrate 1 is transferred to the position of the deceleration sensor 7, it is detected by the deceleration sensor 7 which outputs a signal to the controller 6, and the controller 6 controls the drive motor 2 to decelerate, making the glass substrate 1 to decelerate and continue to go forward. An arrowhead as shown in the drawing indicates the transfer direction of the glass substrate 1.
When the glass substrate 1 continues to go to the position of the positioning sensor 8, it is detected by the positioning sensor 8 which outputs a signal to the controller 6, and the controller 6 controls the drive motor 2 to stop, such that the glass substrate 1 stay at a target position.
In order to prevent detection abnormality of the positioning sensor 8 or abnormality of the drive motor 2 which may cause the glass substrate 1 to flow out of the target position to cause fragmentation, a limit pole 9 is further arranged at the end of the transfer direction of the roller assembly for blocking the glass substrate 1, so as to prevent flowing out of the glass substrate 1.
Further, in order to prevent positioning deviation, the substrate transfer system can also be provided with a moving mechanism for driving the limit pole 9 to move; after the glass substrate 1 is stopped, the limit pole 9 is driven to move by the moving mechanism, and the glass substrate 1 is pushed to move to a predetermined position, thus correcting and confirming the position.
However, the existing substrate transfer system has the following disadvantages at least: 1. because the limit pole 9 is fixedly arranged, the glass substrate 1 is inclined to be fragmented when colliding with the limit pole 9; 2. when the glass substrate 1 goes beyond the predetermined position, the positioning sensor 8 cannot detect it, thus causing the position deviation, proceeding with flowing in this case having a risk of fragmentation; and 3. after the glass substrate 1 is stopped, the limit pole 9 moves over for correcting and confirming the position, during which the glass substrate 1 collides rigidly with the limit pole 9, causing a risk of fragmentation.